Of all the different types of urticaria, probably the rarest type is identified as vibratory angioedema. First of all it should be noted that the word urticaria is nothing more than the medical word for the condition most of refer to as hives. Vibratory angioedema is the rarest form of hives. The cause of it is coming into contact for some prolonged time with a vibratory stimulus. This would normally be a physical vibration such as a vibration that might be put off by a hand tool. Auditory vibration would not be the cause of any of the different types of urticaria.
The vibration could, however, come from something like prolonged rubbing with a towel used to dry off, or from the constant repetitious vibration that may come from running or use of exercise equipment. Of all the types of urticaria categorized as acute, this is usually the most painful. The hives will usually form in a matter of minutes, so the source is pretty easy to identify. Unlike some of the other different types of urticaria, this type will usually disappear in less than an hour.
Solar urticaria types are also rare
Of the many different types of urticaria, solar urticaria is also relatively rare. The parts of the body exposed daily to the sun, like the face or hands, will not develop this type of urticaria. But if you are the type of person who seldom exposes your back or stomach area to the sun, it is possible that you could develop hives in these areas when they are exposed to the sun for any length of time.
This is one of the strangest of the different types of urticaria, in that it will present almost immediately after exposure of the part of the body to the sun. Unlike sunburn, which takes some time, the splotchy areas will appear right away and are caused by a particular solar wavelength. Believe it or not, there are tests that a physician can perform to determine which of the solar wavelengths the culprit is. Once that determination is made, the correct treatment can be determined. It will typically be a sunscreen or antihistamine, but it may be recommended that you gradually increase exposure of the part of the body to the sun to try to build up immunity or tolerance to the sun. Occasionally, it will be recommended that you avoid completely exposing that body area to the sun. Sometimes that is not particularly practical.
So while there are many different types of urticaria, or hives, the vibratory and solar urticaria types are the most unusual and the rarest forms.
